Russian scientists explain appearance of tornadoes and tropical cyclones

Although a large number of researchers have actively studied the problem of destructive atmospheric vortexes for decades, currently there is no satisfactory theory, explaining reasons of appearing, functioning, and natural disappearance of such flows, confirmed both experimentally and by adequate mathematical modelling.

There is no legitimate answer to the main question: from where and into which flow element does exogenous energy investment go, which provides continuous existence of destructive atmospheric vortexes. A mathematical theorem, to which some researchers often refer about non-disappearance of the vertex in the flow, is true only for perfect fluid and perfect gas. In real flows (for example, for revolving water in the glass or for a vortex trail after the plane) curved moves of liquid or gas disappear as the time goes by if there is no exogenous energy investment. They disappear for observable time period. That's why real destructive atmospheric vortexes can't exist without constant exogenous energy investment. We should also note that there is no sufficient explanation of where this energy appears from for initial flow twist.

As the consequence, currently there are no real and reproduced in real tests recommendations on destruction of natural ascending vortex flows, tornadoes and tropical cyclones, with reasonable energy consumptions.

Russian scientists from technical universities, including MEPhI, have conducted a series of theoretical and experimental research and suggested answers to questions "what is the reason of appearing of whirls in natural ascending twisted flows and from where does the energy come for long-lasting self-supported movement of such flows, leading to large devastations and human victims". The results of work, conducted under the supervision of Professor at thr Ural State University of Railway Transport S.P.Bautin, have been published in monography "Destructive atmospheric vortexes and rotation of the Earth about itself". MEPhI was represented in this group by I.Yu. Krutova – Associate Professor of the Department of higher and applied mathematics at the MEPhI branch in Snezhinsk.

Scientists mathematically proved that twisted movement of air with corresponding kinetic energy appears in researched flows only taking into consideration of the Earth rotation about itself. Numerical calculations, represented in the monography, also confirm suggested scheme and correspond with data of conducted field studies.

It has been found out that the necessary condition for appearance of atmospheric vortexes is large and flat space, where an ascending vertical flow is created by external influence (in nature it is solar energy). Earth rotation twists the near-bottom part of the ascending flow, and the twist transmits into the vertical part of the flow. If external influence doesn't destroy this flow during quite a large period of time, the ascending twist flow starts working in a self-sustaining mode, which doesn't require additional heat energy. Destructive atmospheric vortexes, which appeared in nature, receive kinetic energy for twisted air movement only from Earth rotation.

"Obtained analytical, numerical, and experimental results give a good basis for future research in gas dynamic theory of destructive atmospheric vortexes, also for continuation of experimental research on the basis of acquired experience. We are sure that such approaches will allow both us and other researchers move on in the research of this dangerous nature phenomenon," I.Yu. Krutova said.

Provided by National Research Nuclear University